Aggregating particles of wood



Patented Fe. @1 11 T2.

HELIX ILA'UTER, F FLUSHING, NEW YORK, ASSIGNOR TO LIGNEL CORPORATION, A

CORPORATION OF NEW YORK.

AG GGATING PARTICLES 0F WOOD.

We Drawing.

, Tn my co-pending applications, Serial No. 89,7 82, filed February 20, 1926, and Serial No. 229,528, filed October 28, 1927, I describe a 'process whereby the natural resin of wood a may be caused to react with an aldehyde to assist in holding a solid piece of wood in a compressed state.

- According to the present invention, the reaction product between the natural resin in lo the Wood and the formaldehyde is used as a binder to hold together small particles of The sawdust is thoroughly wet with a solu- Y tion of an aldehyde such as formaldehyde or acetaldehyde. Due to the fine state of subdivision the particles of sawdust are impregnated almost immediately. The excess solution is drained off and the sawdust is then dried. The material thus treated is-put in a mold and subjected to pressure at an elevated 0 temperature. The pressure may vary within wide limits; as for example between 800 pounds and 5000 pounds or higher per square inch, but for most purposes a pressure of at' least 1000 pounds to the square inch is advis- 5 able in order that the particles of the Wood may be compressed sutficiently so that the resinous bodies which they contain may be squeezed out to flow over and coverthe surfaces of the particles. The temperature of the mold mplication filed November 18, 1927. Serial'No. 234,300.

or die should be substantially above 212 F. 40

but may be much higher. For example, a temperature of 235 F., or higher, may'be used. The heat and pressure cause the aldehyde and natural resin of the wood to react, forming a hard resinous body which serves as a binder to hold the particles of the wood together. If desired, an .acid or alkaline Iclatllyst may be included with the formalde- The product will have sufficient structural strength to be used for many urposes and its cost will be very low. Saw ust is particularly advantageous in the process both because it is now a waste product and because-it has little or no tendency to felt after being wet, so that it remains in a granular state until pressed, and may readily be handled with automatic machinery. v

What I claim is:

1. The method of aggregating particles of wood which comprises the steps of treating particles of wood containing substantial quantities of natural resin with a solution comprising an aldehyde, dr mg, and then subjecting the wood to the simultaneous action of heat and pressure, whereby the resin of the wood and the aldehyde are caused to react and form a relatively hard binder which unites the particles of wood.

2. A process as defined in claim 1, in which the aldehyde used is formaldehyde.

3. As a new product, a substantially solid mass consisting essentially of particles of compressed wood bound together by the re action products of the natural resinof the Wood and an aldehyde.

' FELIX LAUTER. 

